Device for attaching an insert to a toolholder

ABSTRACT

A device is disclosed for removably attaching an insert to a toolholder having a recessed portion and a shoulder at one end of the recess. The device exerts a force on the insert normal to its upper surface to urge the insert into said recess, while at the same time exerting a second force perpendicular to the first force to urge the insert against the shoulder. The forces are exerted by a system of levers interconnected so as to develop the forces through a single actuator.

United States Patent [191 Mihic June 17, 1975 DEVICE FOR ATTACHING AN INSERT TO A TOOLHOLDER [76] Inventor: Wlajko Mihic, Tegnervagen 9, 802 28 Gavle, Sweden 22 Filed: Apr. 2, 1974 [21] Appl. No.: 457,323

[30] Foreign Application Priority Data Apr. 2, 1973 Sweden 7304579 [52] U.S. Cl. 29/96 [51] Int. Cl B26d 1/00 [58] Field of Search 29/96, 105

[56] References Cited UNITED STATES PATENTS 11/1964 Greenleaf 29/96 Stier 29/96 Milewski 29/96 Primary Examiner-Harrison L. Hinson Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn and Macpeak 5 7] ABSTRACT A device is disclosed for removably attaching an insert to a toolholder having a recessed portion and a shoulder at one end of the recess. The device exerts a force on the insert normal to its upper surface to urge the insert into said recess, while at the same time exerting a second force perpendicular to the first force to urge the insert against the shoulder. The forces are exerted by a system of levers interconnected so as to develop the forces through a single actuator.

9 Claims, 2 Drawing Figures 7 1 DEVICE FOR ATTACHING AN INSERT TO TOOLHOLDER BACKGROUND OF THE INVENTION The present invention comprises a device for a toolholder that accommodates a detachable insert, and it represents a further development of what is presented in Swedish application No. 354,432. Through this document, it is previously known how to equip a toolholder with an angulated lever which, when actedupon by a force transmission means that presses a detachable insert against the bottom of the surface against which the insert lies, also presses the detachable insert against a shoulder face that is largely perpendicular to the bottom, the insert thereby being secured on the toolholder by the pressing force. In this device, the force transmission means should preferably be L-shaped, one of the arms of the L contacting the insert while the other arm contacts the angulated lever, thus causing the clamping force to be distributed throughout the aforesaid seat by a rocking or tilting movement of the force transmission means.

Experience has shown, however, that this arrangement entails certain disadvantages. The clamping device projects considerably above the force transmission means which, in addition to the fact that this is not aesthetically attractive, hinders the removal of chips removed from the workpiece. This is attributable to the fact that the clamping means in order to impart a rocking movement to the force transmission means, transmits force in the form of a highly concentrated spot load to the transmission means thus requiring the clamping means to be provided with a nose that contacts the top surface of the transmission-means, An-

' other significant disadvantage of the aforesaid design is that the aforesaid nose, when it is exposed to the hot removed chips will be deformed and break.

SUMMARY OF THE INVENTION The purpose of this invention is to eliminate the aforesaid disadvantages. This is accomplished by dividing the force transmission means in two interconnected levers operated by a single actuator. A first lever engages the toolholder, and the insert and has an extension which protrudes through the shoulder adjacent a recess in the toolholder. A sleeve is disposed in a bore through the toolholder and engages the extension, a bolt passed through the sleeve and into the toolholder, and serves to retain a second lever in place which engages both the insert and the sleeve.

Thus, rotation of the bolt causes the second lever to exert a downward force on the insert and the sleeve. The sleeve, in turn exerts a downward force on the extension which causes the first lever to bend, thereby exerting a horizontal force on the insert urging it against the shoulder.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a cross sectional view of a device according to the present invention;

FIG. 2 shows a plan view of the device of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawing, represents a toolholder provided with a recess located in its front part, into which is inserted an insert 11 beneath which there may be a support 12. Insert 11 is secured in toolholder 10 by means of a first lever 6 and by means of a second lever l. Lever l is equipped with a forward part 2 that contacts the top surface of insert 11 and presses it against the bottom 18 of the recess in which insert 11 is inserted or against the underlying support 12. The rear part 3 of lever 1 lies against the upper part of a sleeve 4 that surrounds a screw 7 by means of which the clamping force on insert 11 can be regulated. At the front of the sleeve is a lug 5 which acts on the extension 17 of the first lever 6, thereby causing the top portion 16 of first lever 6 to press insert 11 against shoulder face 13. The top part of screw 7 that regulates the clamping force is provided with a head 8 that contacts the top surface of lever 1. Screw 7 is also equipped with a ring 9. The purpose of this ring is, when screw 7 is removed from toolholder 10, to prevent sleeve 4 and second lever 1 from sliding off screw 7. To prevent the rotation of lever 1 relative to sleeve 4 while screw 7 is being turned, sleeve 4, by way of example, can be provided with a recess 19 into which the rear part 3 of lever l enters. Other arrangements are also conceivable, one example being a pin in the lever that engages a hole in sleeve 4.

This invention functions as follows. To secure l1, screw 7 with lever 1 and sleeve 4 is screwed into toolholder 10, whereupon the front part 2 of lever 1 will lie against the top surface of insert 11 and lug 5 on sleeve 4 will contact the first arm 17 on lever 6. Further tightening of screw 7 will now cause screw head 8 to press the front part 2 of lever 1 against insert 11 while the rear part 3 simultaneously presses against the top surface of sleeve 4. This pressing force is propagated via lug 5 to lever 6 which, in turn, presses insert 11 into tighter contact with shoulder face 13. Lever 6 is designed with a slot 14 which enables locating pin 15 and the other parts of first lever 6 to be somewhat resilient relative to each other when a pressing force is applied, while arms 16 and 17 are rigidly integrated. Lug 5 is inserted into a recess in toolholder 10, thus preventing sleeve 4 from rotating relative to toolholder 10.

As can be seen from FIG. 1, the rear part 3 of lever l is formed as a shoulder which is placed in a recess in the sleeve 4. This recess may have a circumferential length which is larger than the width of the shoulder permitting the lever to swing between one position where the lever clamps the insert when tightening the screw and another position where the lever is beside the insert when untightening the screw.

What is claimed is:

1. A device for removably attaching an insert to a toolholder having a recessed portion with a shoulder for engagement with said insert and a plurality of bores through its thickness, said device comprising:

a. a support member in said recess having one edge in alignment with the periphery of a first bore in said toolholder,

b. an insert on top of said support member, said insert having a hole therethrough in alignment with said first bore through the toolholder, one edge of said insert abutting said shoulder,

c. a first lever in said first bore through said toolholder engaging the inner surface of said hole through said insert, said first lever having an extension passing through said shoulder into a second bore through said toolholder,

d. a sleeve disposed in said second bore engaging said extension of said first lever,

e. a second lever engaging said insert and said sleeve,

and

f. means to move said second lever toward said toolholder such movement exerting a force on said insert tending to hold it against said shoulder. 2. The device of claim 1 wherein the means to move said second lever acts on said second lever between the portion engaging said insert and said portion engaging said sleeve.

3. The device of claim 2 wherein said means to move said second lever comprises a bolt threadingly engaged with said second bore.

4. The device of claim 3 wherein said bolt has a locking ring about its periphery below said sleeve to prevent disengagement of said sleeve and said second lever from said bolt when saidbolt is removed from said toolholder.

5. The device of claim 1 wherein said first lever has a second extension engaging said support member.

6. The device of claim 1 wherein said sleeve has a lug protruding from one side, said lug engaging said extension of said second lever.

7. The device of claim 5 wherein said lug also engages a recess in the wall of said second bore to prevent rotation of said sleeve relative to said toolholder.

'8. The device of claim 1 wherein the second lever engages a slot in the top of said sleeve, the width of said slot being wider than the portion of the second lever engaging the slotso as to permit said second lever to move laterally with respect to said sleeve.

9. The device of claim 1 wherein said first lever has a slot partially extending along its length from the end nearest said insert. 

1. A device for removably attaching an insert to a toolholder having a recessed portion with a shoulder for engagement with said insert and a plurality of bores through its thickness, said device comprising: a. a support member in said recess having one edge in alignment with the periphery of a first bore in said toolholder, b. an insert on top of said support member, said insert having a hole therethrough in alignment with said first bore through the toolholder, one edge of said insert abutting said shoulder, c. a first lever in said first bore through said toolholder engaging the inner surface of said hole through said insert, said first lever having an extension passing through said shoulder into a second bore through said toolholder, d. a sleeve disposed in said second bore engaging said extension of said first lever, e. a second lever engaging said insert and said sleeve, and f. means to move said second lever toward said toolholder such movement exerting a force on said insert tending to hold it against said shoulder.
 2. The device of claim 1 wherein the means to move said second lever acts on said second lever between the portion engaging said insert and said portion engaging said sleeve.
 3. The device of claim 2 wherein said means to move said second lever comprises a bolt threadingly engaged with said second bore.
 4. The device of claim 3 wherein said bolt has a locking ring about its periphery below said sleeve to prevent disengagement of said sleeve and said second lever from said bolt when said bolt is removed from said toolholder.
 5. The device of claim 1 wherein said first lever has a second extension engaging said support member.
 6. The device of claim 1 wherein said sleeve has a lug protruding from one side, said lug engaging said extension of said second lever.
 7. The device of claim 5 wherein said lug also engages a recess in the wall of said second bore to prevent rotation of said sleeve relative to said toolholder.
 8. The device of claim 1 wherein the second lever engages a slot in the top of said sleeve, the width of said slot being wider than the portion of the second lever engaging the slot so as to permit said second lever to move laterally with respect to said sleeve.
 9. The device of claim 1 wherein said first lever has a slot partially extending along its length from the end nearest said insert. 